Spark gap



Feb. 13, 1934. w. ILBERG 1,946,695

SPARK GAP Filed May 6, 1931 INVENTOR WALDE R ILBERG BY W ATTORNEY gapswhich serve for the Patented Feb. 13, 1934 PATENT OFFICE SPARK GAPWaldemar Ilberg, Berlin,

Telefunken Gesellschaft graphic m. b. 11., Berlin,

tion of Germany Application May 6, 1

Germany, assignor to fur Drahtlose Tele- Germany, a corpora- 931, SerialNo. 535,392,

and in Germany May 6, 1930 4 Claims.

This invention relates to a spark-gap for the production of ultra-shortelectrical oscillations or Waves.

The present invention is concerned with sparkgeneration of very shortelectrical waves, say, of a length less than around 2 meters. Theproduction of such short waves by means of one or more spark-gapsnowadays is attended with serious difiiculties as soon as the generationof relatively large energies is dealt with. This is due to the slightinterelectrode distance (order of magnitude of 0.1 mm.) which must beused, as is well known from practical experience, in order to result inactive sparks. Such a small distance between the electrodes in continualoperation can be maintained without readjustment of the spark-gap onlyif the wear of the electrode material is small; in other words, if theintensity of the sparks is kept small. Another drawback residing insmall interelectrode distances consists in that the sparking potentialis comparatively low and that as a consequence this also makes for lowenergetic efliciency of the spark-gap. The invention hereinafter to bedisclosed has the object to overcome both of the said disadvantages ofthe ordinary spark-gap in that both the life as well as the energyconversion are augmented.

With this end in view, according to the invention, the spark-gap is tobe surrounded with the atmosphere of an indifferent gas such as hydrogenor helium which will not chemically attack the material of theelectrodes even in the heat. By the adoption of this scheme the wear andtear of the electrodes is diminished in the desired manner so that thepreservation of a small interelectrode distance is insured also for longtimes. If deemed necessary and advantageous, the gas to be used forsurrounding the gap may be of high thermal conductivity inasmuch as thisprecludes the destructive action caused by the heating of theelectrodes.

To be sure, the idea has been quite frequently expressed and carriedinto practice to place quenched spark-gaps in the atmosphere of a gasother than air; but arrangements 01' this kind have heretofore been usedfor far greater wave lengths, and the same was used for another purposethan the one hereinbefore dis closed. The main object in such earlierarrangements invariably has been to expedite deionization of the gas ordischarge gap by insuring rapid abduction of heat, say, by an atmosphereof hydrogen, illuminating gas or alcohol vapors in order to thus enhancethe quenching effect of the spark-gap. In the invention here disclosed,however, the question of insuring good quenching action plays a whollysecondary part inasmuch as due to the high radiation damping inherent inshort waves the adoption of the principle 0 discharges, since 10 theglass vessel wherein the two electrodes 3 7 and 3' are accommodated andmounted by means of two pins 2 and 2' serving as supply leads.

I claim:

1. An ultra short wave spark gap comprising a hermetically sealedbarrel-shaped glass vessel,

a pair of electrodes spaced substantially .1 mm. apart and supportedwithin said vessel, an atmosphere of hydrogen within said vessel andsurrounding said electrodes.

2. A spark gap for the generation of ultra short electric wave lengthsof less than 2 meters, comprising a hermetically sealed barrel-shapedglass vessel, a pair of electrodes having curved sparking surfacesmounted within said vessel,

connecting means passing through the walls of said glass vessel, and anatmosphere of helium contained within said vessel.

3. A spark gap for the generation of ultra short electric wave lengthsof less than 2 meters, comprising a closed cylindrical glass vessel, 2.pair of curved metallic electrodes spaced substantially .1 mm. apartfrom each other, mounted within said vessel, connecting leads passingthrough a thickened portion of the wall of said glass vessel, and anatmosphere of helium contained within said vessel.

4. Apparatus for the use in ultra short wave circuits, comprising ahermetically sealed cylindrical glass vessel containing helium gas underpressure, a pair of curved electrodes spaced apart from each other andsupported by the wall of said vessel, said electrodes being arrangedwithin said vessel to act as a spark gap for the generation of ultrahigh frequency currents.

WALDEMAR ILBERG.

